The present invention relates to automatic milking machines and, more particularly, to apparatus for automatically cleansing the interior of a cow milking teat cup cluster between the milking of successive cows therewith.
In automatic milking, a cluster of teat cups are applied to a cow's udder, a pulsating pneumatic or vacuum source is applied to the teat cups to effect milking, and the resulting milk is drawn by a vacuum from the cluster to a milk collection tank. Typically, a plurality of such clusters are connected to the milk receptacle to enable a plurality of cows to be milked simultaneously. However, there are generally many more cows than there are clusters with the result that each individual cluster is used to milk a plurality of successive cows.
Use of a single teat cup cluster successively for different cows during a milking operation can result in the spread of disease through a dairy herd. More particularly, any bacteria or other infectious material on the teats of one cow can be transmitted by the cluster teat cups to any cow with which such cluster is later used. While this problem has been recognized for some time, no effective solution to the same has been forthcoming. That is, although those in the art recognize the desirability of cleansing a teat cup cluster between uses with successive cows, no practical apparatus or method for effecting such cleansing has been devised. In this connection, it is all-important that the cleansing method and apparatus be one which assures that neither the cleansing fluid nor any other contaminant can be mixed with the milk. The use of a simple valving arrangement to isolate the milk receptacle from a teat cup cluster during the cleaning operation is not practical, since residual cleansing fluid on the internal surfaces of the valves typically will mix with milk emanating from the next cow to be milked. Moreover, there is concern that valve failure or the like may result in undetected contamination of milk already in the collection tank.